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1.
Microbiol Spectr ; 12(7): e0023924, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38785430

RESUMO

Hepatitis B virus (HBV), a common blood transmission pathogen worldwide, can lead to viral hepatitis, cirrhosis, liver cancer, and other liver diseases. In particular, occult hepatitis B virus infection (OBI) may be caused by an immune response leading to suppressed virus replication. Gut microbiota can change the immunity status of the human body and, therefore, affect the replication of HBV. Thus, to identify whether there are differences in gut microbiota between HBV carriers and OBI carriers, we collected fecal samples from 18 HBV carriers, 24 OBI blood donors, and also 20 healthy blood donors as negative control. After 16S sequencing, we found that the abundance of Faecalibacterium was significantly reduced in samples from OBI blood donors compared with those from healthy blood donors. Compared with samples from HBV carriers, the samples from OBI blood donors had a significantly increased abundance of Subdoligranulum, which might stimulate immune activation, thus inhibiting HBV replication and contributing to the formation of occult infection. Our findings revealed the potential role of gut microbiota in the formation of OBI and further provided a novel strategy for the treatment of HBV infection.IMPORTANCEOccult hepatitis B virus infection (OBI) is a special form of hepatitis B virus infection with hepatitis B surface antigen (HBsAg) positive and hepatitis B virus (HBV) DNA negative. Gut microbiota may contribute to the immune response leading to suppressed virus replication and, thus, participates in the development of OBI. The study on gut microbiota of OBI blood donors provides novel data considerably advancing our understanding of the immune mechanism for the determination of occult hepatitis B virus infection, which is helpful for improving the strategy of the treatment of HBV infection.


Assuntos
Fezes , Microbioma Gastrointestinal , Vírus da Hepatite B , Hepatite B , Humanos , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Masculino , Hepatite B/virologia , Hepatite B/microbiologia , Hepatite B/imunologia , Adulto , Feminino , Fezes/microbiologia , Fezes/virologia , Pessoa de Meia-Idade , Portador Sadio/microbiologia , Portador Sadio/virologia , DNA Viral/genética , Replicação Viral , Antígenos de Superfície da Hepatite B/sangue , RNA Ribossômico 16S/genética , Adulto Jovem , Doadores de Sangue , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética
2.
J Environ Manage ; 356: 120616, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518493

RESUMO

Metakaolin-based geopolymers are very promising materials for improving the safety of low and intermediate level radioactive waste disposal, with respect to ordinary Portland cement, due to their excellent immobilization performance for Cs+ and superior chemical stability. However, their application is limited by the fact that the leaching behavior of Cs+ is susceptible to the presence of other ions in the environment. Here, we propose a way to modify a geopolymer using perfluorodecyltriethoxysilane (PDFS), successfully reducing the leaching rate of Cs+ in the presence of multiple competitive cations due to blocking the diffusion of water. The leachability index of the modified samples in deionized water and highly concentrated saline water reached 11.0 and 8.0, respectively. The reaction mechanism between PDFS and geopolymers was systematically investigated by characterizing the microstructure and chemical bonding of the material. This work provides a facile and successful approach to improve the immobilization of Cs ions by geopolymers in real complex environments, and it could be extended to further improve the reliability of geopolymers used in a range of applications.


Assuntos
Resíduos Radioativos , Eliminação de Resíduos , Reprodutibilidade dos Testes , Polímeros , Eliminação de Resíduos/métodos , Íons
3.
Telemed J E Health ; 29(12): 1769-1780, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37093158

RESUMO

Introduction: The coronavirus disease 2019 (COVID-19) pandemic has created lots of difficulties for individuals to seek medical help offline. Telehealth is considered as a potential approach to solve this issue. During the COVID-19 pandemic, although the use of telehealth has increased in the short term, it still remains unknown whether the use of telehealth can maintain a high level of development in the long term. The purpose of this article is to investigate the impact of COVID-19 pandemic on telehealth use across time and regional medical resources. Materials and Methods: Our research used the Internet search index from Baidu Index Platform in 31 provinces of China as the proxy of telehealth use. A total of 2,119,486 times of searching behaviors from January 2018 to December 2021 are included in our dataset. Changing plots, the method of analysis of variance and empirical models are applied to reveal the relationship between COVID-19 pandemic and telehealth use. Results: Baidu Index counts increased (p < 0.01) at the beginning of COVID-19 pandemic (2020) but started to decline (p < 0.01) during the period of regular epidemic prevention and control (2021). Moreover, the counts of Baidu Index in regions with rich medical resources are higher than those in other regions in 2020. Comparing Baidu Index counts in 2020, the COVID-19 pandemic has higher positive effects on telehealth use during the period of 2021 in regions with average and poor medical resources. Conclusions: COVID-19 pandemic has a positive effect on telehealth use in 2020 but has a negative effect in 2021. During the epidemic, telehealth use differs in regions with rich, average, and poor medical resources. Our findings indicate that the use of telehealth should be promoted with different measures in regions with different medical resources, thereby contributing its healthy development in the long term.


Assuntos
COVID-19 , Telemedicina , Humanos , COVID-19/epidemiologia , Pandemias/prevenção & controle , Nível de Saúde , Telemedicina/métodos , China/epidemiologia
4.
J Hazard Mater ; 443(Pt B): 130161, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36327833

RESUMO

Geopolymers (GPs) have emerged as promising adsorbents for wastewater treatment due to their superior adsorption stability, tunable porosity, high adsorption capacity, and low-energy production. Despite their great promise, developing GPs with well-controlled hierarchical structures and high porosity remains challenging, and the mechanism underlying the ion adsorption process remains elusive. Here we report a cost-effective and universal approach to fabricate Na or K GPs with sophisticated architectures, high porosity, and arbitrary cation species exchange by means of additive manufacturing and a surfactant. The introduction of sodium lauryl sulfate (SLS) enhanced the porosity of the GP adsorbents, yielding NaGP-lattice-10%SLS adsorbent with a high total porosity of 80.8 vol%. Combining static and dynamic adsorption tests, the effects of morphology, surfactant content, and cation species on Cs+ adsorption performance were systemically investigated. With an initial Cs+ concentration of 900 mg/L, the printed NaGP exhibited a maximum Cs+ adsorption capacity of 80.1 mg/g, outperforming other adsorbents reported so far. The quasi-second-order fit of the NaGP adsorbent showed overall higher R2 values than the quasi-first-order fit, indicating that the adsorption process was dominated by ion exchange. Combined with first-principles calculations, we verified that the content of water in the GP sod cages also affected the ion-exchange process between Na+ and Cs+.

5.
J Hazard Mater ; 384: 121377, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31629598

RESUMO

Notwithstanding the success of carbon-free nuclear power in the new energy industry, an effective way to address nuclear contamination is still lacking. As a generally accepted method to date, immobilization of radioactive nuclear wastes with inexpensive and environment-friendly matrix such as geopolymer has attracted extensive attention. In this contribution, Na-based and K-based metakaolin geopolymer were prepared to encapsulate simulated radioactive Cs+ and Sr2+ under different temperatures and environments during long-term leaching tests. The temperature-dependent and environmental-dependent leaching kinetics as well as their dominant leaching mechanisms have been revealed. The results showed that Na-based and K-based geopolymer exhibited better immobilization performance than that of Portland cement, ceteris paribus. For the immobilization of Cs+, Na-based geopolymer showed lower leaching rate than K-based geopolymer under the same leaching conditions. Both higher temperature and salt solution accelerated the leaching behaviors of Sr+ and Cs2+ from the encapsulation matrix. This contribution sheds light on understanding the dominant leaching mechanisms of hazardous elements under different storage environments and highlights the significance of salt-tolerant matrix for the immobilization of nuclear wastes.

6.
J Med Internet Res ; 21(3): e12156, 2019 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-30900997

RESUMO

BACKGROUND: In recent years, paid online patient-physician interaction has been incorporated into the telemedicine markets. With the development of telemedicine and telemedicine services, online feedback has been widely applied, helping other patients to identify quality services. Recently, in China, a new type of service feedback has been applied to the telemedicine markets, namely, paid feedback. Patients who are satisfied with a physician's online service can buy a virtual gift or give a tip to the physicians. This paid feedback can improve the reliability of service feedback and reduce the proportion of false information because it increases the cost for feedback providers. Paid online feedback can benefit the physicians, such as by providing them with monetary incentives; however, research on the impacts and value of such paid feedback from the physician perspective in the telemedicine markets is scant. To fill this research gap, this study was designed to understand the role of paid feedback by developing a research model based on the theories of signaling and self-determination. OBJECTIVE: This study aimed to explore the effects of free and paid feedback on patients' choice and physicians' behaviors as well as to investigate the substitute relationship between these 2 types of feedback in the telemedicine markets. METHODS: A JAVA software program was used to collect online patient-doctor interaction data over a 6-month period from a popular telemedicine market in China (Good Physician Online). This study drew on a 2-equation panel model to test the hypotheses. Both fixed and random effect models were used to estimate the combined effects of paid feedback and free feedback on patients' choice and physicians' contribution. Finally, the Hausman test was adopted to investigate which model is better to explain our empirical results. RESULTS: The results of this study show that paid feedback has a stronger effect on patients' choice (a5=0.566; t2192=9.160; P<.001) and physicians' contribution (ß4=1.332; t2193=11.067; P<.001) in telemedicine markets than free feedback. Moreover, our research also proves that paid feedback and free feedback have a substitute relationship in determining patients' and physicians' behaviors (a6=-0.304; t2191=-5.805; P<.001 and ß5=-0.823; t2192=-8.136; P<.001). CONCLUSIONS: Our findings contribute to the extant literature on service feedback in the telemedicine markets and provide insight for relevant stakeholders into how to design an effective feedback mechanism to improve patients' service experience and physicians' engagement.


Assuntos
Pacientes/psicologia , Médicos/psicologia , Telemedicina/economia , Análise de Dados , Tomada de Decisões , Retroalimentação , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Telemedicina/métodos
7.
Telemed J E Health ; 25(7): 591-598, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30096267

RESUMO

Introduction: In the past decades, the average weight of residents has increased significantly. Weight management has become an important issue in our society. With the developments of mobile technology and applications, mobile health applications (m-health apps) provide a convenient platform for users to engage in weight loss tasks and control their body weight. However, due to the lack of proper motivators, engaging in weight loss tasks on m-health apps is stressful for the users. The aim of this study is to understand why users engage in weight loss tasks, and to be specific, we establish an empirical model to examine the effects of social motivators (social support) and personal motivators (body condition) and their interactive relationship on the level of user engagement using self-determination theory. Materials and Methods: We developed a JAVA software program and automatically downloaded 1,138 users' information from an m-health app. Following, we used these data to calculate variables of our research model, including body mass index (BMI), informational support, emotional support, and the level of engagement in weight loss tasks. Additionally, we used the Ordinary Least Squares to estimate our research model. We also checked the robustness of the results by dividing the data into different groups. Results: The empirical results of our research model indicate that informational and emotional supports are positively associated with the engagement levels of users in weight loss tasks. Additionally, we have found out that body condition (using BMI as a proxy) has a U-shaped relationship effect on users' engagement. Furthermore, our research proves that body condition and informational support have a substitutive relationship in affecting user engagement. Conclusions : These findings can contribute to the literature concerning online weight loss and to provide suggestions for users and practitioners of m-health apps, catering different incentive mechanisms to users with different body condition to help them control their body weight.


Assuntos
Aplicativos Móveis , Apoio Social , Redução de Peso , Adolescente , Adulto , Índice de Massa Corporal , Pesos e Medidas Corporais , China , Emoções , Feminino , Objetivos , Educação em Saúde/métodos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Telemedicina/métodos , Adulto Jovem
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